The present invention relates generally to drinking straws, and more particularly, to a bendable double-walled insulated drinking straw for use in drinking hot and cold liquids.
Numerous drinking straws have been designed for use in drinking liquid beverages. There are conventional tubular drinking straws, flexible drinking straws, extendable drinking straws that are used to project into milk and orange juice containers, and straws attached to helmets and other devices.
While such conventional drinking straws are designed for drinking cold liquids, none of these devices are particularly well-suited for drinking hot liquids. In particular, coffee drinkers purchase cups of coffee which are drunk on the way to work or while walking around. The cups have lids on them with an opening or openings in them that permit the person to sip the coffee. However, it is very easy to accidentally spill the coffee when drinking from these types of cups, which results in hot coffee spilling onto clothes and skin.
Another problem is that conventional straws which could be used to drink hot beverages are not insulated. Consequently, one""s fingers can be scalded or at least feel uncomfortable when drinking hot beverages through them.
The drinking straw disclosed in U.S. patent application Ser. No. 09/433,627, filed Nov. 3, 1999 provides for a unique plastic drinking straw wherein outer and inner tubular members are secured or welded together in the middle area of the straw. It would be an improvement to have a straw similar to the straw disclosed in U.S. patent application Ser. No. 09/433,627, but which is bendable so that it may be folded in any direction to about 90 degrees.
Accordingly, it is an objective of the present invention to provide for a double-walled bendable insulated drinking straw that may be used to drink liquids, and in particular, hot liquids.
To accomplish the above and other objectives, the present invention provides for a bendable double-walled insulated drinking straw that may be used to consume liquids. The present invention is particularly well-suited for use in drinking hot liquids, especially hot liquids that are normally consumed from a cup or other similar container.
The bendable insulated drinking straw comprises an inner tubular member, such as an inner tubular plastic straw, for example, and an outer tubular insulating member, such as an outer tubular plastic straw, for example, that is separated from and provides insulation for the inner tubular member. The outer tubular insulating member is attached or fused to the inner tubular member at a predetermined sealing or attachment location that is separated from respective ends of the straw. A flexible joint is formed at the sealing location that allows a portion of the straw on one side of the joint to articulate with respect to a portion of the straw on the other side of the joint.
The outer tubular insulating member may be attached to the inner tubular member by sealing or melting the two members together in the area of the sealing or attachment location. Preferably, the tubular members are sealed along a length of the straw that is on the order of from one-half inch to one inch, or so. In accordance with the present invention, the sealed portion of the straw is processed so that it has a folding section or joint located at the sealed area of the straw, corresponding to the sealing or attachment location.
To make the double walled straw bendable, a plurality of circular grooves that generally are parallel to each other are formed in the sealed section, for example. The sealed section may be made folding by processing the double-walled straw using the teachings of U.S. Pat. No. 4,613,474, issued Sep. 23, 1986, for example.
The relative cross sections of the outer tubular insulating member and the inner tubular member may be such that fluid is sipped using the inner tubular member while the outer tubular insulating member is held by the person drinking the fluid. Also, the diameter of the outer tubular insulating member is such that a persons lips are in contact with it and not the inner tubular member.
The bendable double-walled insulated drinking straw of the present invention is not limited to any particular cross section. Thus, round, elliptical, square, rectangular, triangular or other shaped tubular members may be constructed using the principles of the present invention.
The outer tubular insulating member may be formed to have a cross section that matches the cross section of the inner tubular member, although this is not absolutely required. The outer tubular insulating member may be connected to the inner tubular member by means of a plurality of ribs or a serpentine member. Other interconnection members may readily be used.
The space between the inner tubular member and the outer tubular insulating member may be air, or may be filled with or comprise an insulating material. Any suitable insulating material may be used. Typical insulating materials include elastomeric materials, such as butyl, ethylene, propylene, fluorocarbon, fluorosilicone, neoprene, nitrile, silicone and thermoplastic elastomer, polyolefin tubing, polytetrafluroethylene (PTFE), polystyrene, resin, polyurethane, sponge, cellular silicone, and foam, for example.
The bendable double-walled insulated drinking straw is particularly well suited for use in drinking hot liquids, and is inserted into a cup or container holding the hot liquid. The upper exposed portion of the straw outside the container may be bent to a suitable angle via the folding section of the straw, and the outer tubular insulating member may be grasped while drinking the hot beverage, without the risk of burning one""s fingers or one""s lips. When the insulated drinking straw is used with a container of hot liquid, there is no need to tip the container to drink the liquid, which minimizes the possibility of accidental spillage. The outer tubular insulating member also minimizes heat transferred to one""s fingers and lips so that scalding is minimized.